<?php
//图像处理类
class ImageCrop{
 private $file;    //图片地址
 private $width;   //图片长度
 private $height;   //图片长度
 private $type;    //图片类型
 private $img;    //原图的资源句柄
 private $new;    //新图的资源句柄
 
 //构造方法，初始化
 public function __construct($_file) {
     
    // p_e(11111111);
  $this->file =$_file;
  list($this->width, $this->height, $this->type) = getimagesize($this->file);
  $this->img = $this->getFromImg($this->file, $this->type);
 }
 //缩略图(固定长高容器，图像等比例，扩容填充，裁剪)[固定了大小，不失真，不变形]
 public function thumb($new_width = 0,$new_height = 0) {
  
  if (empty($new_width) && empty($new_height)) {
   $new_width = $this->width;
   $new_height = $this->height;
  }
  
  if (!is_numeric($new_width) || !is_numeric($new_height)) {
   $new_width = $this->width;
   $new_height = $this->height;
  }
  
  //创建一个容器
  $_n_w = $new_width;
  $_n_h = $new_height;
  
  //创建裁剪点
  $_cut_width = 0;
  $_cut_height = 0;
  
  if ($this->width < $this->height) {
   $new_width = ($new_height / $this->height) * $this->width;
  } else {
   $new_height = ($new_width / $this->width) * $this->height;
  }
 
  
  
  
  if ($new_width < $_n_w) { //如果新高度小于新容器高度
   $r = $_n_w / $new_width; //按长度求出等比例因子
   $new_width *= $r; //扩展填充后的长度
   $new_height *= $r; //扩展填充后的高度
   $_cut_height = ($new_height - $_n_h) / 2; //求出裁剪点的高度
  }
  
  if ($new_height < $_n_h) { //如果新高度小于容器高度
   $r = $_n_h / $new_height; //按高度求出等比例因子
   $new_width *= $r; //扩展填充后的长度
   $new_height *= $r; //扩展填充后的高度
   $_cut_width = ($new_width - $_n_w) / 2; //求出裁剪点的长度
  }
   
  
  $this->new = imagecreatetruecolor($_n_w,$_n_h);
  imagecopyresampled($this->new,$this->img,0,0,$_cut_width,$_cut_height,$new_width,$new_height,$this->width,$this->height);
 }
 
 //加载图片，各种类型，返回图片的资源句柄
 private function getFromImg($_file, $_type) {
  switch ($_type) {
   case 1 :
    $img = imagecreatefromgif($_file);
    break;
   case 2 :
    $img = imagecreatefromjpeg($_file);
    break;
   case 3 : 
    $img = imagecreatefrompng($_file);
    break;
   default:
    Tool::alertBack('警告：此图片类型本系统不支持！');
  }
  return $img;
 }
 
 //图像输出
 public function out() {
  imagepng($this->new,$this->file);
  imagedestroy($this->img);
  imagedestroy($this->new);
 }
}
 
 
 

?>
